The present invention relates to an endotracheal tube connector for connecting an endotracheal tube to a source of oxygen or other gas, and more particularly to an endotracheal tube connector having a relatively large gas inlet and a generally funnel shaped portion for reducing the work of breathing by an intubated patient.
In general, the endotracheal tube connectors in current use have a common configuration. For example, the configuration consists basically of a pair of cylindrical barrels which share a common longitudinal axis. The first barrel, i.e. the gas inlet, has an outside diameter of about 15 mm and is adapted to receive a flexible tube having an inside diameter of about 15 mm forced over the barrel for connecting the endotracheal tube to a source of oxygen.
The second barrel, or gas outlet, of the currently used connectors has an inside diameter of about 8 mm which is the same as the inside diameter of an endotracheal tube. One end of the endotracheal tube, i.e. the end that protrudes from the mouth of a patient, is forced over the second barrel in order to insure an airtight fit, maximum gas flow and minimum resistance. In fact, the outside diameter of the outlet barrel is typically tapered at the patient end to facilitate insertion of the tubular member into the endotracheal tube and minimize turbulence as the gas passes from the connector into the endotracheal tube.
A number of problems with currently used configurations have arisen. For example, it is sometimes difficult to insert the connector into an endotracheal tube. Gupga U.S. Pat. No. 4,146,034 addresses this problem by providing a bevelled cut from the top of the connector to a point between the center line of the connector and the bottom thereof. Thus, the bevelled edge taken together with the tapered portion facilitates attaching the connector to an endotracheal tube and tends to minimize air turbulence as the gas flows from the connector into the endotracheal tube.
However, it appears that none of the prior art addresses the more serious problem which relates to the work of breathing with an endotracheal tube in place and the difficulty in removing seriously ill patients from a respirator. Removing a weakened patient from a respirator requires a patient to breath on their own and overcome the resistance of the tube and the connector. Also, it is frequently necessary to have the patient inhale oxygen enriched air and or a gas containing medication. Apparently, no one has addressed the problem of minimizing obstructions and air turbulence at the inlet end of the connector or as the oxygen enriched air is pulled or inhaled into and through the connector.
It has now been found that an improved connector according to the present invention can significantly reduce the work of breathing by reducing the negative pressure required to inhale a given volume of oxygen enriched gas. It has also been found that connectors in accordance with the present invention can be readily used with most commercially available endotracheal tubes, are relatively inexpensive to produce and relatively easy to attach to an endotracheal tube and/or to a source of oxygen or medicated vapor as selected by the physician.
In addition, the connectors disclosed herein take optimum advantage of the basic physical considerations to reduce as much as possible the resistance to breathing a patient experiences when a tracheal tube is positioned in his or her trachea and attached to a source of oxygen or the like, and thereby reduces patient discomfort, trauma and may avoid life threatening consequences.